Paramore frontwoman Hayley Williams has been left seething after a hacker invaded her Twitter account and posted a topless picture of the star online. A photo of the singer lying on a bed and baring her breasts appeared on the social networking site on Thursday evening, sending fans into a flurry. The explicit image was quickly deleted, and Williams later explained she had been the victim of an internet prankster. In a post on her Twitter.com page, she explains, “Well… my night just changed drastically. Got hacked.”